2. SqueakGTK
• Presentation of GTK+
• GLib
• GDK, Pango, Cairo
• GTK+
• SqueakGTK tools (Omnibrowser, launcher)
• To do
• Conclusions
3. GTK+
• Open source toolkit (LGPL)
• Created for the GIMP
• Written in C
• Multi platform
4. GTK+
X11 Win32 (Quartz)
GLib
GDK Pango Cairo
Figure 2.9: The GTK+ stack
All parts of the GTK+ stack are written in C, and hence there is no support for object-orientation
features in the language. GTK+ still boasts itself as an object-oriented toolkit. This is thanks to
GObject, which is a part of GLib.
GObject is an object system which is used extensively by GTK+. It is designed to be easy to be
used by other programming languages, both interpreted and compiled.
GObject supports object inheritance as well as interfaces. Objects can also have named properties.
There also exists a general purpose notification mechanism for objects called signals.
GTK+ Stack
5. GLib
• Cross platform utility
• Linked list, hash tables, binary trees, ...
• C object model : GObject
• Fundamental types (Float, String, ...)
• Enumeration
6. GObject
• Single inherited class structure
• Signals
• Independent type system (GType)
• Memory management : reference counting
